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Summary 1.From September 2003, acute National Health Service trusts in England have been required by the Department of Health to undertake mandatory surveillance of bacteraemias caused by glycopeptide-resistant enterococci (GRE). 2.In total, 4855 enterococcal bacteraemias (including 256 reports of ‘Group D streptococci') were reported through the voluntary reporting system to the Communicable Disease Surveillance Centre (CDSC) in England and Wales in 2002, and 8.9% of the reports that contained information on vancomycin susceptibility indicated that the isolate was resistant to vancomycin. Most hospitals reported fewer than five GRE bacteraemias per year to the CDSC, with only 13 hospitals reporting more than five episodes per year, although there is undoubtedly an element of under-reporting. 3.This Working Group was established to review the methods used to identify and test the susceptibility of enterococci to glycopeptides, and to make recommendations on the reporting of GRE bacteraemias, as there were indications that current methods would not provide a suitable basis for this surveillance. 4.A review of methods was undertaken, including a national questionnaire on methods, approaches to testing and risk factors for GRE bacteraemia. This, together with data from routine laboratory reports and special surveys, revealed the following. –A significant proportion of enterococci are not identified to species level. –There are problems with identification of enterococci. Commercially available kits do not identify some enterococcal species reliably. –Not all laboratories test vancomycin susceptibility of enterococci from bacteraemia. This does not allow a robust assessment of GRE bacteraemia rates because the prevalence of glycopeptide resistance will be underestimated if laboratories test teicoplanin alone or no glycopeptides against enterococci. –There are technical difficulties in detecting non-VanA resistance in enterococci and this will also contribute to under-reporting of glycopeptide resistance. 5.Clinically significant GRE infection is associated with a worse prognosis than infection with susceptible strains, but this factor has not been clearly separated from the possible influence of co-morbidities and antibiotic usage. 6.GRE bacteraemia occurs mainly on specialist units, particularly transplantation, renal, haematological malignancy and intensive care units. Hospitals with such units will inevitably have a higher risk of featuring prominently in surveillance studies. Hence, meaningful denominators for surveillance of GRE bacteraemia are required. Recommendations for GRE bacteraemia surveillance 1.As the mandatory surveillance of glycopeptide-resistant enterococci (GRE) bacteraemias has already started, this report recommends a phased approach to some of the developments, such as using meaningful denominators for the bacteraemia rates. 2.Rates of GRE bacteraemias in trusts should not be used as a performance indicator because the numbers are too small for valid analysis in this way. 3.GRE bacteraemias as a proportion of all clinically significant bacteraemias in the trust should be measured as an indicator of changing trends. 4.Since most GRE are likely to be associated with specialist units, reports of GRE bacteraemia should indicate the specialty in which the patient acquired the infection. 5.Data on clinical activity in the special units where patients acquired GRE bacteraemias should be obtained from trusts with more than five GRE bacteraemias in a year. 6.The significance of blood cultures containing GRE should be assessed clinically. If the bacteraemia that includes GRE is deemed to be clinically significant (according to the case definitions for bacteraemia), whether mono- or polymicrobial, it should be reported as a GRE bacteraemia. 7.Enterococci from blood cultures should be identified to species level to provide data on resistance rates in different species. 8.Biochemical identification should be augmented by antimicrobial susceptibility patterns. The identification is suspect if Enterococcus faecalis appears to be ampicillin resistant and/or quinupristin/dalfopristin susceptible, or if Enterococcus faecium appears to be ampicillin susceptible and/or quinupristin/dalfopristin resistant. The identification and susceptibility of such isolates should be checked and, if confirmed, the isolate should be sent to a reference laboratory for further investigation. 9.Enterococci from blood cultures should be tested for susceptibility to vancomycin. Teicoplanin is not an acceptable alternative to vancomycin for these purposes. 10.Standardized methods should be used for glycopeptide susceptibility testing of enterococci, and the technical requirements of the methods must be adhered to. 11.The situation should be reviewed after a year and the methodology should be amended as appropriate. Recommendations for further research 1.A group should be established to explore methods of data collection for global and individual risk factors for GRE bacteraemia. 2.Further studies on the performance of commercial identification kits with a range of enterococcal species are necessary. 3.Further studies to improve the reliability of susceptibility testing methods for detection of GRE are necessary.

The increase since the mid 1980s in glycopepetide resistant enterococci (GRE) raised concerns about the limited options for antimicrobial therapy, the implications for ever-increasing numbers of immunocompromised hospitalised patients, and fuelled fears, now realised, for the transfer of glycopeptide resistance to more pathogenic bacteria, such as Staphylococcus aureus. These issues underlined the need for guidelines for the emergence and control of GRE in the hospital setting. This Hospital Infection Society (HIS) and Infection Control Nurses Association (ICNA) working party report reviews the literature relating to GRE prevention and control. It provides guidance on microbiological investigation, treatment and management, including antimicrobial prescribing and infection control measures. Evidence identified to support recommendations has been categorized. A risk assessment approach is recommended and areas for research and development identified.

These evidence-based guidelines have been produced after a literature review of the laboratory diagnosis and susceptibility testing of methicillin-resistant Staphylococcus aureus (MRSA). We have considered the detection of MRSA in screening samples and the detection of reduced susceptibility to glycopeptides in S. aureus. Recommendations are given for the identification of S. aureus and for suitable methods of susceptibility testing and screening for MRSA and for S. aureus with reduced susceptibility to glycopeptides. These guidelines indicate what tests should be used but not when the tests are applicable, as aspects of this are dealt with in guidelines on control of MRSA. There are currently several developments in screening media and molecular methods. It is likely that some of our recommendations will require modification as the new methods become available.

To describe the current patterns and trends in antimicrobial susceptibility in enterococci and streptococci (excepting pneumococci) from bacteraemia in the UK and Ireland from 2001 to 2006.In each year 2001-06, blood culture isolates were collected by 25 laboratories distributed across the UK and Ireland. In total, there were 1408 isolates of enterococci, 1332 of beta-haemolytic streptococci and 1012 of alpha- and non-haemolytic streptococci. A single central laboratory re-identified the isolates and measured MICs by the BSAC agar dilution method.The prevalence of reduced susceptibility in streptococci and enterococci did not change significantly for most antibiotics, but trends were noted to increased ampicillin, imipenem and vancomycin resistance in Enterococcus faecium. The prevalence of reduced susceptibility to macrolides and tetracycline in streptococci, to tetracycline and gentamicin (high level) in enterococci and to beta-lactams and glycopeptides in E. faecium were all high, with some differences in the prevalence among species or groups.Reduced susceptibility to some antimicrobial agents among streptococci and enterococci remains common and continued surveillance is warranted.

BackgroundClostridium difficile is a leading infectious cause of health care associated diarrhoea. Several industrialised countries have reported increased C. difficile infections and outbreaks, which have been attributed to the emergent PCR ribotype 027 strain.Methods and findingsWe conducted a case-case study to compare severity of C. difficile disease for patients with 027 versus non-027 ribotypes. We retrospectively collected clinical information about 123/136 patients with C. difficile infections admitted to hospitals in the East of England region in 2006 and from whom stool isolates were cultured and ribotyped as part of an earlier national survey. We defined severe C. difficile disease as having one or more of shock, paralytic ileus, pseudo membranous colitis or toxic megacolon. Patient median age was 83 years old (range 3 to 98, interquartile range 75 to 89), 86% were prescribed antibiotics in the eight weeks before illness onset, 41% had ribotype 027 and 30-day all cause mortality during hospital admission was 21%. Severe disease occurred in 24% (95%CI 13% to 37%) and 17% (95%CI 9% to 27%) of patients with PCR ribotype 027 and non-027 ribotypes respectively. In a multivariable model, ribotype 027 was not associated with severe disease after adjusting for sex, discharge from hospital prior to 60 days of current admission, gastroenteritis on admission, number of initiator antibiotics for C. difficile disease, and hospital where the patient was admitted.ConclusionsOur study found no evidence to support previous assertions that ribotype 027 is more virulent than other PCR ribotypes. This finding raises questions about the contribution of this strain to the recent increase in C. difficile disease throughout North America and Europe.